Personal Blogs

On 23 October 2024 I attended something called a Go Green Workshop which was all about ‘Dirty Digital Habits’. Having recently supported a research intern who had been exploring what is meant by green computing, the topic of sustainable computing (and all that means) has become of increasing interest. The event had an alternative title: Go Green Spotlight - Digital Carbon Footprints. Apparently, this month is ‘cyber awareness month’. A lot of the session was facilitated by David Crews, our Digital Services Sustainability lead, with input from other colleagues.

A number of topics were covered in the hour long session. These were, broadly: challenges, current efforts, what we can do, and something about a search engine called Ecosia. I share a bunch of reflections at the end.

Challenges 

The full title of this topic was ‘challenges in reducing digital related CO2 emissions’. There was a passing reference to a Guardian article about data centres but there was also a passing comments that data centres would consume 8% of electricity by 2030. This suggested figure is likely to be under threat due to increases in cloud computing, and AI. I noted another challenging comment that was shared, which was: by 2025, everyone will have an interaction with a data centre every 18 seconds. I have no idea where this striking estimate comes from, but I now need to find out.

Current efforts

The full title of this section was ‘current efforts in digital services to reduce CO2 emissions’. In other words, what was the university doing? More specifically, what is ‘digital services’ doing?

During this bit of the workshop, I noted down a few points. One continual action that was being taken was addressing of legacy systems. There was a reference to the scheduled replacement of hardware, with the suggestion that newer hardware means better energy efficiency (I did later ask a question that asked whether the carbon cost of equipment manufacture, and disposal was also taken account of).

There was also a reference to a movement of services from university data centres to data centres managed by third party suppliers (two different vendors were mentioned). On this point, I also noted down the words “a cloud data centre is more efficient than anything that an organisation can run themselves”. The point is, of course, that that energy costs of our own data centres are likely to be higher than the costs of cloud suppliers.

A number of familiar topics were mentioned, such as the movement to different processor architectures on servers (such as ARM processors, the kind of chips that you find on your mobile phone), the use of virtual machines to make optimal use of hardware, and the importance of having your data (and servers) as close to the users as possible. Closeness improves latency (performance) and reduces energy consumption.

On a related note, I was introduced the PUE measurement, which is an abbreviation for Power Usage Effectiveness (Wikipedia). The lower the number, the more efficient your data centre is. I need to look into this in a bit more depth.

What can we do?

Under this heading, I combined notes from two different parts of the presentation which had the titles ‘how we can contribute at home’ and ‘top categories to reduce your digital carbon footprint’. Some of the suggestions were familiar: use energy efficient peripherals, power things off, go paperless, stop hoarding data (particularly on the cloud), and ask ourselves whether we really need to use super high definition data when streaming film. In the work environment, when having team calls, can we get away with only using audio? This obviously reduces how much data we use. Also, use browser bookmarks rather than searching for a website address using search engines. An interesting statistic was shared: a search using Google will use 14g of CO2, a kettle takes 15g (but I don’t have the reference from where this comes from; I need to find it).

An interesting question was highlighted: what is the carbon cost of email? It depends, of course, on the length and the content of an email message. A practical suggestion was to minimise the use of attachments. A further interesting statistic was that 71% of colleagues make use of email attachments rather than linking to files. Shipping files across and between email accounts makes unnecessary use of data storage.  A file sent through email can use 50g of CO2 (again, I don’t know where this statistic comes from). Sharing a link rather than an attachment can mean a 90% reduction. Of course, the choice of attachment vs link very much depends on whether we have continual access to the cloud services that we need to use. 

Ecosia: Search engine pilot

Towards the end of the session, a search engine called Ecosia was mentioned. More information about Ecosia is available through a useful Wikipedia summary. The reason for mentioning it is that there is a plan to pilot its use as the default search engine.

Reflections

I feel as if I must have missed something. I had never heard of an OU unit called ‘digital services’ before; I’ve always known it as IT (in the same way that I know People Services as HR). 

This wasn’t an academic event, and it was less of a workshop and more of a presentation (since the time allocated to discussion was quite limited). I did feel that there was quite a need to discuss digital practices. Also, wearing an academic hat, I have an intrinsic need to look for the sources that relate to the statistics that were shared.

I appreciated the presentation about the carbon cost of email. This discussion reflects a similar question I have, which is: what is the carbon cost of taking a digital photograph? There probably isn’t a simple answer: it would depend on how that photograph is used (and how it is shared). 

Given that energy consumption is now important to business units such as digital services, I did wonder about whether there will become a time where organisations may be required to report their energy use. To what extent may statutory reporting be helpful or appropriate? Is this desirable or useful? There’s that old engineering adage of if you can measure something, you can then control it.

Within all this, there’s the need for balance. There’s the need to balance the need to minimise using digital bandwidth with the importance of maintaining and fostering personal connections. There’s also the need to use additional layers of software to maintain security and integrity of systems (such as virus checkers and intruder detection systems), whilst minimising a software stack to reduce server costs. There’s the balance of necessarily carrying out searches to attempt to solve a problem, contrasted with the inherent carbon cost of carrying out searches. 

One of the points that I asked about was the physical (environmental) cost of changing hardware. Electronics contain a huge amount of embedded carbon, which comes its design and manufacture. How is electronic hardware safely and responsibly disposed? Also, how to we make the most effective ‘carbon’ decisions about to migrate from one hardware platform to another?  Should this come under the remit of software engineering? Are there some standards or guidelines that can be help with decision making?

Tone of this event was very positive. Perhaps it’s my state of mind, but this positivity doesn’t reflect my own understanding of the term ‘climate emergency’. It’s important to consider how we consume digital resources, just as we consume physical resources. Individuals can, of course make a difference, but if individual decisions are not measured (in the way that the use of the Ecosia search engine may be measured), then it’s hard to measure what difference we may have made.

I’m going to have to search for some references.

Many thanks to everyone in Digital Services for facilitating a thought provoking event.

It takes far too long for my desktop PC to finish booting up every morning.  From the moment I throw the power switch of my aging XP machine to the on position and click on my user name, I have enough time to walk to the kitchen, brew a cup of tea, do some washing and tidying up and drink half my cup of tea (or coffee), before I can begin to load all the other applications that I need to open before settling down to do some work.

I would say it takes over fifteen minutes from the point of power up to being able to do some 'real stuff'.  All this hanging around inevitably sucks up quite a bit of needless energy.  Even though I do have some additional software services installed, such as a database and a peer-to-peer TV application, I don't think my PC is too underpowered (it's a single core running just over a gigahertz with half a gig of memory).

Being of a particular age, I have fond memories of the time when you turned on a computer, the operating system (albeit a much simpler one) was almost instantly available. Ignoring the need to load software from cassettes or big floppy disks, you could start to issue commands and do useful stuff within seconds of powering up.

This is one of the reasons why I like my EEE netbook (Wikipedia): if I have an idea for something to write or want to talk to someone or find something out, then I can turn it on and within a minute or two it is ready for use. (As an aside, I remember reading in Insanely Great by Steven Levy (Amazon) the issue of boot up time was an important consideration when designing the original Macintosh).

Green Code

These musings make me wonder about the notion of 'green code': computer software that is designed in such a way that it supports necessary functionality by demanding a minimal amount of processor or memory resources. Needless to say, this is by no means an original idea. It seems that other people are thinking along similar lines.

In a post entitled, Your bad code is killing my planet, Alistair Croll writes, 'Once upon a time, lousy coding didn't matter. Coder Joel and I could write the same app, and while mine might have consumed 50 percent of the machine's CPU whereas his could have consumed a mere 10 percent, this wasn't a big deal. We both paid for our computer, rackspace, bandwidth, and power.'

Croll mentions that software is often designed in terms of multiple levels of abstraction. He states that there can be a lot of 'distance and computing overhead between my code and the electricity of each processor cycle'. He goes on to write, 'Architecture choices, and even programming language, matter'. Software architecture choices do matter and abstractions are important.

Green Maintenance

Making code that is efficient is only part of the story. Abstractions allow us to hide complexity. They help developers to compartmentalise and manage the 'raw thought stuff' which is computer code. Well designed abstractions can give software developers who are charged with working and maintaining existing systems a real productivity boost.

Code that is easier to read and work with is likely to be easier to maintain. Maintenance is important since some researchers' report that maintenance accounts for up to 70% of costs of a software project.

In my opinion, clean code equals green code. Green code is code that should be easy to understand, maintain and adapt.

Green Challenges

Croll, however, does have a point. Software engineers should need to be aware of the effect that certain architectural choices may have on final system performance.

In times when IT budgets may begin to be challenged (even though IT may be perceived as technology that can help to create business and information process efficiencies), the request for an ever more powerful server may be frowned upon by those who hold the budgetary purse strings. You may be asked to do more with less.

This challenge exposes a fundamental computing dilemma: code that is as efficient as it could be may be difficult to understand and work with. Developers have to consider such challenges carefully and walk a careful path of compromise. Just as there is an eternal trade off between speed of a system and how much power is consumed, there is also a difficult trade offs to consider in terms of efficiency and clarity, along with the dimensions of system flexibility and functionality.

One of the reasons why Microsoft Vista is not considered to be popular is the issue of how resource hungry it is in terms of memory, processor speed and disk drive space. Microsoft, it seems is certainly aware of this issue (InfoWorld).

Turning off some of the needless eye candy, such as neatly shaded three dimensional buttons, can help you to get more life out of your PC. This is something that Ted Samson mentions, before edging towards discussing the related point of power management.

Ted also mentions one of those well known laws of computing. He writes, 'just because there are machines out there that can support enormous system requirements doesn't mean you have to make your software swell to that footprint'. In other words, 'your processor and disk space needs expands to the size of your machine' (another way of also saying 'your project expands to the amount of time you have available'!)

Power Budgets

Whilst I appreciate my EEE PC in terms of its quick boot up time, it does have an uncomfortable side effect: it also acts as a very effective lap warmer. Even more surprisingly, its batteries are entirely depleted within slightly over two hours of usage. A mobile device should not be tethered to a mains power supply. It also makes me wonder about whether its incessant demand for power is going to cut short the life of its batteries (which represent their own environmental challenge).

When working alongside electrical engineers, I would occasionally over hear them discussing power budgets, i.e. how much power would be consumed by components of a larger electrical system. In terms of software, both laptop and desktop PC offer a range of mysterious software interfaces that provide 'power management' functionality. This is something that I have not substantially explored or studied. For me, this is an area of modern PCs that remain a perpetual mystery. It is certainly something that I need do to something about.

Sometimes, the collaboration between software developers and hardware engineers can yield astonishing results. I again point towards the One Laptop per Child project. I remember reading some on-line discussions that described changes that were made to the Linux operating system kernel to make the OLPC device more power efficient. A quick search quickly throws up an Environmental Impact page.

The OLPC device, whether you agree with the objective of the OLPC project or not, has had a significant impact on the design of laptop systems. A second version of the device raises the possibility of netbooks using the energy efficient ARM processor (Wikipedia) - the same processor that is used (as far as I understand) in the iPhone and iPod I, for one, look forward to using a netbook that doesn't unbearably heat up my lap and allows me to do useful work without having to needless wasted time searching for power sockets.

My desktop computer (which was assembled by my own fair hands) produces a side effect that is undeniably useful during the winter months: it perceptibly heats up my room almost allowing me to totally dispense with other forms of heating completely (but I must add that a chunky jumper is often necessary). When I told someone else about this phenomenon, I was asked, 'big computer or small room?' The answer was, inevitably, 'small room' (and small computer).

Google

On a related note, I was recently sent a link to a YouTube video entitled Google container data centre tour. It was astonishing (and very interesting!) It was astonishing due to the sheer scale of the installation that was presented, and interesting in terms of the industrial processes and engineering that were described. It reminded me of a news item that was featured in the media earlier this year that related to the carbon cost of carrying out a Google search.

The sad thing about the Google data centre (and, of course, most power plants) is that most of the heat that is generated is wasted. I recently came across this article, entitled Telehouse to heat homes at Docklands. Apparently there are other schemes to use data centres for different kinds of heating.

Before leaving Google alone, you might have heard of a site called Blackle. Blackle takes the Google homepage and inverts it. The argument is that if everyone uses a black search page, large power savings can be made.

Mark Ontkush describes the story of Black Google and others in a very interesting blog post which also mentions other useful ideas, such as the use of Firefox extensions. Cuil is another search engine (pronounced 'cool') that embodies the same idea.

Carbon Cost of Spam

I recently noticed a news item entitled Spam e-mails killing the environment (ITWorld). Despite the headline having a passing resemblance to headlines that you would find on the Daily Mail, I felt the article was worth a look. It references a more sensibly titled report, The carbon footprint of email spam, published by McAfee.

The report is interesting, pointing towards the fact that that we may spend a lot of time both reading and processing junk emails that end up in our inbox. The article has an obvious agenda: to sell spam filters. An effective spam filter, it is argued, can reduce the amount of time that email users spend processing spam, thus helping to save the planet (a bit). Spam can fill up email servers, causing network administrators to use bigger disks. To be effective, email servers need to spend time (and energy) filtering through all the messages that are received. I do sense that more research is required.

Invisible Infrastuctures

There is a further connection between the challenge of spam and the invisible infrastucture of the internet. Messages to your PC, laptop or mobile device pass through a range of mysterious switches, routers and servers. At each stage, energy is mysteriously consumed and paid for by an invisible set of financial transactions.

My own PC, I should add, is not as power friendly as it could be. It contains two hard disk drives: a main drive that contains the operating system, and a secondary drive that contains backup files and also 'swap' area. The main reason for the second drive is to gain a performance boost.

Lower power PCs

After asking the question, 'how might I create an energy efficient PC', I discovered an interesting article from Ars Technica entitled It's easy being green. It describes each of the components of a PC and considered how much power they can draw. The final page features a potential PC setup in the form of 'an extreme green box'.

It is, however, possible to go further. The Coding Horror blog presents one approach: use kit that was intended for embedded systems - a domain where power consumption is high on the design agenda. An article, entitled Building Tiny, Ultra Low Power PCs is a fun read.

Both articles are certainly worth a view. One other cost that should be considered, however, is the cost of manufacturing (and also recycling) your existing machine. I don't expect to change my PC until the second service pack for Windows 7 is released. It's going to be warming my room for quite some time, but perhaps the carbon consumption stats that relate to PC manufacture and disposal are out there somewhere that may help me to make a decision.

Concluding thoughts

Servers undeniably cost a lot of money not only in terms of their initial purchase price, but also in terms of how much energy they consume over their lifetime.

Efficient software has the potential to reduce server count, allowing more to be achieved with less. Developers should aspire to write code that is as efficient as possible, and take careful account of the underlying software infrastructures (and abstractions) that they use. At the heart of every software development lies a range of challenging compromises. It often takes a combination of experience and insight to figure out the best solution, but it is important to take account of change since the majority of the time on any software system is likely to be during the maintenance phase of a software project.

The key to computing energy reduction doesn't only rest with computer scientists, hardware designers and software engineers. There are wider social and organisational issues at play, as Samson hints at in an article entitled No good excuses not to power down PCs. The Open University has a two page OU Green computing guide that makes a number of similar points.

One useful idea is to quantify computer power in terms of megahertz per miliwatt (MPMs) instead of millions of instructions per second (MIPS) - I should add that this isn't my idea and I can't remember where it came from. It might be useful to try to establish a new aspirational computing 'law'. Instead of constantly citing Moore's law which states that the number of transistors should double every two years, perhaps we need to edge towards trying to propose a law that proposes a reduction in power consumption whilst maintaining 'transactional performance'. In this era of multi-core multi-function processors, this is likely to be a tough call, but I think it's worth a try.

One other challenge is whether it might be possible to crystalise what is meant by 'green code', and whether we can explore what it means by constructing good or bad examples. The good examples will run on low powered slower hardware, wherease the bad examples will likely to be sluggish and unresponsive. Polling (constantly checking to see whether something has changed) is obviously bad. Ugly, inelegant, poorly structured and hard to read (and hard to change) code could also be placed in a box named 'bad'.

A final challenge lies with whether it might be possible to explore what might be contained within a sub-discipline of 'green computing'. It would be interesting to see where this might take us.